v2.4.0.6

FAIR VALUE MEASUREMENTS (Tables) | 3 Months Ended
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Mar. 31, 2012
FAIR VALUE MEASUREMENTS [Abstract] |
Fair Value, Measurement Inputs, Disclosure [Text Block] | The following assets and liabilities are measured at fair value:
| March 31, 2012
| Level 1 |  | Level 2 |  | Level 3 |  | Total
| (Thousands of Dollars)
Other current assets: |  |  |  |  |  |  |
Product imbalances | $ | 1,661 |  |  | $ | — |  |  | $ | — |  |  | $ | 1,661 |
Commodity derivatives | 21,880 |  |  | 329 |  |  | — |  |  | 22,209 |
Other long-term assets, net: |  |  |  |  |  |  |
Commodity derivatives | — |  |  | 5,377 |  |  | — |  |  | 5,377 |
Interest rate swaps | — |  |  | 581 |  |  | — |  |  | 581 |
Accrued liabilities: |  |  |  |  |  |  |
Product imbalances | (200 | ) |  | — |  |  | — |  |  | (200 | )
Commodity derivatives | (13,692 | ) |  | (24,500 | ) |  | — |  |  | (38,192 | )
Interest rate swaps | — |  |  | (9,796 | ) |  | — |  |  | (9,796 | )
Other long-term liabilities: |  |  |  |  |  |  |
Commodity derivatives | — |  |  | (6,539 | ) |  | — |  |  | (6,539 | )
Interest rate swaps | — |  |  | (11,221 | ) |  | — |  |  | (11,221 | )
Total | $ | 9,649 |  |  | $ | (45,769 | ) |  | $ | — |  |  | $ | (36,120 | )
| December 31, 2011
| Level 1 |  | Level 2 |  | Level 3 |  | Total
| (Thousands of Dollars)
Other current assets: |  |  |  |  |  |  |
Product imbalances | $ | 2,117 |  |  | $ | — |  |  | $ | — |  |  | $ | 2,117 |
Commodity derivatives | 10,282 |  |  | 1,830 |  |  | — |  |  | 12,112 |
Other long-term assets, net: |  |  |  |  |  |  |
Commodity derivatives | — |  |  | 27,084 |  |  | — |  |  | 27,084 |
Interest rate swaps | — |  |  | 2,335 |  |  | — |  |  | 2,335 |
Accrued liabilities: |  |  |  |  |  |  |
Product imbalances | (1,469 | ) |  | — |  |  | — |  |  | (1,469 | )
Commodity derivatives | (5,424 | ) |  | — |  |  | — |  |  | (5,424 | )
Interest rate swaps | — |  |  | (22,009 | ) |  | — |  |  | (22,009 | )
Other long-term liabilities: |  |  |  |  |  |  |
Interest rate swaps | — |  |  | (27,190 | ) |  | — |  |  | (27,190 | )
Total | $ | 5,506 |  |  | $ | (17,950 | ) |  | $ | — |  |  | $ | (12,444 | )
Fair Value and Carrying Value of Debt [Text Block] | The estimated fair value and carrying amount of our debt was as follows:
| March 31, 2012 |  | December 31, 2011
| (Thousands of Dollars)
Fair value | $ | 2,575,496 |  |  | $ | 2,377,565 |
Carrying amount | $ | 2,521,412 |  |  | $ | 2,293,030 |

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- Definition Fair Value and Carrying Value of Debt [Text Block] + References No definition available. + Details
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- Definition Tabular disclosure of the fair value measurement of assets and liabilities which includes [financial] instruments measured at fair value that are classified in stockholders' equity. Such assets and liabilities may be measured on a recurring or nonrecurring basis. The disclosures which may be required or desired include: (1) for assets and liabilities measured on a recurring basis, disclosure may include: (a) the fair value measurements at the reporting date; (b) the level within the fair value hierarchy in which the fair value measurements in their entirety fall, segregating fair value measurements using quoted prices in active markets for identical assets or liabilities (Level 1), significant other observable inputs (Level 2), and significant unobservable inputs (Level 3); (c) for fair value measurements using significant unobservable inputs (Level 3), a reconciliation of the beginning and ending balances, separately presenting changes during the period attributable to the following: (i) total gains or losses for the period (realized and unrealized), segregating those gains or losses included in earnings (or changes in net assets), and a description of where those gains or losses included in earnings (or changes in net assets) are reported in the statement of income (or activities); (ii) purchases, sales, issuances, and settlements (net); (iii) transfers in and transfers out of Level 3 (for example, transfers due to changes in the observability of significant inputs); (d) the amount of the total gains or losses for the period in subparagraph (c) (i) above included in earnings (or changes in net assets) that are attributable to the change in unrealized gains or losses relating to those assets and liabilities still held at the reporting date and a description of where those unrealized gains or losses are reported in the statement of income (or activities); (e) the valuation technique(s) used to measure fair value and a discussion of changes in valuation techniques, if any, during the period and (2) for assets and liabilities that are measured at fair value on a nonrecurring basis (for example, impaired assets) disclosure may include, in addition to (a) above: (a) the reasons for the fair value measurements recorded; (b) the same as (b) above; (c) for fair value measurements using significant unobservable inputs (Level 3), a description of the inputs and the information used to develop the inputs; and (d) the valuation technique(s) used to measure fair value and a discussion of changes, if any, in the valuation technique(s) used to measure similar assets and/or liabilities in prior periods. Where the quoted price in an active market for the identical liability is not available, the Level 1 input is the quoted price of an identical liability when traded as an asset. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 820 -SubTopic 10 -Section 50 -Paragraph 3 -URI http://asc.fasb.org/extlink&oid=6925170&loc=d3e19279-110258 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 157 -Paragraph 32 -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 157 -Paragraph 33 -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 107 -Paragraph 10 -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. Reference 5: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 820 -SubTopic 10 -Section 50 -Paragraph 5 -URI http://asc.fasb.org/extlink&oid=6925170&loc=d3e19296-110258 Reference 6: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 820 -SubTopic 10 -Section 50 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=6925170&loc=d3e19207-110258 Reference 7: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 157 -Paragraph 6 -Footnote 4 -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. Reference 8: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 820 -SubTopic 10 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6925170&loc=d3e19190-110258 + Details
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